Large-scale plant for producing green hydrogen by electrolyzing water

Abstract

The utility model belongs to the field of electrochemistry, and particularly relates to a large-scale factory for producing green hydrogen by electrolyzing water. The electrochemical green hydrogen production factory comprises a large-scale water electrolysis green hydrogen production system, and the large-scale water electrolysis green hydrogen production system comprises an energy supply system (1), a rectification system (2), an electric pile group (3), an alkali liquor tank (4), a total liquid supplementing tank (5), a hydrogen gas-liquid separation tower (61), a hydrogen washing tower (62), a hydrogen storage tank (63), an oxygen gas-liquid separation tower (71), an oxygen washing tower (72), an oxygen storage tank (73) and a cooling water system (8). The electrochemical green hydrogen production plant is small in pollution, low in energy consumption and low in cost, and large-scale industrialization of green hydrogen production and oxygen production is facilitated.

Description

Technical Field

[0001] The utility model belongs to the field of electrochemistry, and particularly relates to a large-scale electrolyzed water green hydrogen production plant. Background Art

[0002] With the progress of human civilization and the development of the economic society, mankind is facing the challenges of the decreasing of fossil energy such as coal, oil and natural gas and the increasingly serious environmental pollution. Mankind has to make the dual-carbon strategic goal.

[0003] Although the thermal catalysis technology plays a leading role in traditional large-scale petrochemical industry, fine chemical industry, environmental governance, etc., the electrochemical process has also been widely applied in large-scale industrialization in several important traditional industries such as the chlor-alkali industry, the smelting of light metals such as aluminum / sodium, the refining of metals such as copper / zinc, and the surface finishing of components in the machinery industry due to its advantages of flexible regulation of the electric field to regulate reaction thermodynamics and kinetics, relatively mild reaction conditions, and simple operation.

[0004] Theoretically, by means of the electrochemical process, by changing the voltage direction between the positive and negative electrodes, the directional conversion of electrical energy and chemical energy stored in various chemical bonds can be realized; at the same time, by regulating the overpotential between the positive and negative electrodes, the conversion rate of electrical energy-chemical energy can be flexibly regulated; furthermore, different from the traditional heat engine process, the electrochemical process is theoretically not limited by the Carnot cycle and has a higher theoretical energy conversion efficiency. Due to the above advantages, today when fossil energy is decreasing and environmental pollution is becoming increasingly serious, the electrochemical industry is playing an increasingly important role in many important fields such as modern industrial production and residents' life in new energy, energy storage, electronic products, transportation power, etc.

[0005] From the perspective of large-scale chemical industry, the current electrolyzed water hydrogen production has problems such as being relatively small-scale, not low in pollution, high in energy consumption, and high in cost, which is also one of the fundamental reasons for the low current green hydrogen production capacity.

[0006] Therefore, there is still an urgent need for a method for preparing green hydrogen with large scale, low pollution, low energy consumption, and low cost. Content of the Utility Model

[0007] To solve the above technical problems, the utility model provides the following technical solutions.

[0008] In the first aspect, the utility model provides a large-scale electrolyzed water green hydrogen production plant.

[0009] A large-scale electrolyzed water green hydrogen production plant, which includes: a large-scale electrolyzed water green hydrogen production system, and the large-scale electrolyzed water green hydrogen production system includes an energy supply system 1, a rectification system 2, an electrolytic stack group 3, an alkali liquid tank 4, a second replenishing liquid tank 122, a total replenishing liquid tank 5, hydrogen processing related devices 6, oxygen processing related devices 7, and a cooling water system 8;

[0010] The hydrogen treatment related device 6 includes a hydrogen gas-liquid separation tower 61, a hydrogen scrubbing tower 62 and a hydrogen storage tank 63;

[0011] The oxygen treatment related device 7 includes an oxygen gas-liquid separation tower 71, an oxygen scrubbing tower 72 and an oxygen storage tank 73;

[0012] The cooling water system 8 includes a multi-functional cooling water tank 81, a first heat exchanger 82 and a second heat exchanger 83;

[0013] The energy supply system 1 supplies power to the stack group 3 for electrolyzing water;

[0014] The lye tank 4 can provide electrolyte for the stack group 3 through pipelines to electrolyze water to obtain hydrogen and oxygen. The hydrogen obtained by electrolysis and the electrolyte flowing out with the hydrogen can be subjected to gas-liquid separation in the hydrogen gas-liquid separation tower 61. The separated hydrogen can be further purified by washing in the hydrogen scrubbing tower 62. The hydrogen purified by washing can be stored in the hydrogen storage tank 63 after being cooled by the first heat exchanger 82. The electrolyte separated by the hydrogen gas-liquid separation tower 61 and / or the first washing liquid obtained after being purified by washing in the hydrogen scrubbing tower 62 can be aggregated, filtered and pH-adjusted through the total replenishing tank 5, and then re-provide electrolyte for the stack group 3 to electrolyze water. Through the recycling of the electrolyte, the waste liquid discharge can be minimized, the water consumption can be reduced, the system energy consumption can be reduced, and the cost can be saved;

[0015] The oxygen obtained by electrolysis and the electrolyte flowing out with the oxygen can be subjected to gas-liquid separation in the oxygen gas-liquid separation tower 71. The separated oxygen can be further purified by washing in the oxygen scrubbing tower 72, and then stored in the oxygen storage tank 73 after being cooled by the second heat exchanger 83. The electrolyte separated by the oxygen gas-liquid separation tower 71 and / or the second washing liquid obtained after being purified by washing in the oxygen scrubbing tower 72 can be aggregated, filtered and pH-adjusted through the total replenishing tank 5, and then re-provide electrolyte for the stack group 3 to electrolyze water. Through the recycling of the electrolyte, the waste liquid discharge can be minimized, the water consumption can be reduced, the system energy consumption can be reduced, and the cost can be saved.

[0016] In some embodiments, the large-scale electrolyzed water to produce green hydrogen system intelligent adaptive control system 9.

[0017] In some embodiments, the current of the energy supply system 1 passes through the intelligent adaptive control system 9 and is shunted to the rectification systems 2 of each column to supply power to the stack group 3 for electrolyzing water.

[0018] In some embodiments, the total liquid replenishment tank 5 is provided with a first filter 51 and / or a first purification device 58. The electrolyte obtained by separating in the hydrogen gas-liquid separation tower, the electrolyte purified by washing in the hydrogen scrubbing tower 62, the electrolyte obtained by separating in the oxygen gas-liquid separation tower 71, and the second washing liquid obtained by washing and purifying in the oxygen scrubbing tower 72 can be filtered by the first filter 51 and / or the first purification device 58 on the total liquid replenishment tank when passing through the total liquid replenishment tank.

[0019] In some embodiments, a first filter 51 and / or a first purification device 58 are provided between the hydrogen gas-liquid separation tower 61 and the hydrogen scrubbing tower 62 and the total liquid replenishment tank. The electrolyte obtained by separating in the hydrogen gas-liquid separation tower 61 and / or the first washing liquid obtained by washing and purifying in the hydrogen scrubbing tower 62 can be filtered by the first filter 51 and / or the first purification device 58 before entering the total liquid replenishment tank.

[0020] In some embodiments, a first filter 51 and / or a first purification device 58 are provided between the oxygen gas-liquid separation tower 71 and the oxygen scrubbing tower 72 and the total liquid replenishment tank 5. The electrolyte obtained by separating in the oxygen gas-liquid separation tower 71 and / or the second washing liquid obtained by washing and purifying in the oxygen scrubbing tower 72 can be filtered by the first filter 51 and / or the first purification device 58 before entering the total liquid replenishment tank.

[0021] In some embodiments, the separated oxygen can be further washed and purified with water in the oxygen scrubbing tower 72. In some embodiments, the separated oxygen can be further washed and purified with the water in the multi-functional cooling water tank 81 in the oxygen scrubbing tower 72.

[0022] In some embodiments, the separated hydrogen can be further washed and purified with water in the hydrogen scrubbing tower 62. In some embodiments, the separated hydrogen can be further washed and purified with the water in the multi-functional cooling water tank 81 in the hydrogen scrubbing tower 62.

[0023] In some embodiments, the energy supply system 1 is a renewable energy energy storage system. Using a renewable energy energy storage system as the energy supply system 1 is beneficial to reducing the use of fossil raw materials such as coal and petroleum and reducing carbon emissions. In addition, the energy supply system 1 can play a buffering role between energy production and energy consumption to cope with the problem of unstable renewable energy power generation.

[0024] In some embodiments, the energy source of the renewable energy energy storage system is hydropower, wind power or solar energy.

[0025] In some embodiments, the intelligent adaptive control system 9 is an intelligent response system that can monitor the operating status of each column or each battery stack 31, including status parameters such as current, voltage, power, liquid level, and temperature, and adjust the voltage and current allocated to each column or each battery stack according to the renewable energy power generation situation, self-adjust the operating status of each column or each battery stack 31, and timely adjust the number of battery stack switch vehicles and the corresponding operating power to match the volatility of renewable energy power generation. In addition, the intelligent adaptive control system 9 can also respond to feedback on abnormal working conditions of the battery stack 31 in the battery stack group 3, and stabilize the working state of the entire system by adjusting the operating parameters of other electrolytic cells / mobile area electrolytic cells.

[0026] In some embodiments, the multifunctional cooling water tank 81 can store cooling water, and the cooling water in the multifunctional cooling water tank 81 can flow to the first heat exchanger 82 and the second heat exchanger 83 through a pipe; the water passing through the first heat exchanger 82 or the water passing through the second heat exchanger 83 replenishes the total fluid replenishment tank 5 and / or flows back to the multifunctional cooling water tank 81.

[0027] In some embodiments, the fuel cell group 3 consists of at least two fuel cell stacks 31 .

[0028] In some embodiments, the battery stack 31 includes a power source, an anode 312 , a separator 313 , a cathode 319 and a plate frame 320 .

[0029] In some embodiments, the battery stack 31 further includes an electrolyte inlet 314 , an electrolyte outlet 315 , an anode gas outlet 316 , and a cathode gas outlet 317 .

[0030] In some embodiments, at least one or at least two battery stacks 31 are connected in parallel to form a battery stack unit 321, and the battery stack group 3 is composed of at least two battery stack units 321 connected in series; the battery stacks 31 in each battery stack unit 321 are connected in parallel through a pipeline for providing electrolyte, and the circuits of each battery stack 31 in each battery stack unit 321 are independently controlled. There is a multifunctional fluid replenishment tank 12 between each battery stack unit 321, and the multifunctional fluid replenishment tank 12 can filter, replenish and adjust the pH of the electrolyte flowing out of the previous battery stack unit 321, and then provide electrolyte to the next battery stack unit 321; finally, the electrolyte of the battery stack unit 321 can be collected, filtered, replenished and adjusted in pH through the main fluid replenishment tank 5, and then flow back to each multifunctional fluid replenishment tank 12 to provide electrolyte for the battery stack group 3 for water electrolysis.

[0031] In some embodiments, each stack 31 in each stack unit 321 further includes an independently controlled backup power supply 318. In some embodiments, each stack 31 in each stack unit 321 further includes an independently controlled backup power supply 318. The current provided by the energy supply system 1 is directly supplied to the stack 31 for electrolysis or supplied to the backup power supply 318, and then the backup power supply 318 supplies it to the stack 31 for electrolysis.

[0032] In some embodiments, the multifunctional liquid replenishing tank 12 is provided with a second filter 121 and / or a second purification device 128. The electrolytic solution obtained by separating in the hydrogen gas-liquid separation tower, the electrolytic solution obtained by separating in the oxygen gas-liquid separation tower 71, and the second washing liquid obtained after being washed and purified by the oxygen washing tower 72 can be filtered by the second filter 121 and / or the second purification device 128 on the multifunctional liquid replenishing tank when entering the multifunctional liquid replenishing tank.

[0033] In some embodiments, the multifunctional liquid replenishing tank 12 is formed by connecting a second gas-liquid separator 127, a second filter 121 and / or a second purification device 128, and a second liquid replenishing tank 122 in series.

[0034] In some embodiments, the total liquid replenishing tank 5 is formed by connecting a first gas-liquid separator 57, a first filter 51 and / or a second purification device 128, and a first liquid replenishing tank 52 in series.

[0035] In some embodiments, the operating voltage of each stack 31 in each stack unit 321 can be independently controlled respectively. According to the renewable energy power generation, the number and voltage of the stacks for operation can be flexibly adjusted to match the energy storage requirements at different times and cope with the intermittency and volatility of renewable energy power generation. Specifically, the stack group 3 can be divided into two working areas. One working area is the non-motorized working area, and the stacks in the non-motorized working area maintain a stable operating voltage; the other is the motorized working area, and the stack voltage in the motorized working area is controlled by the intelligent adaptive control system 9 and is flexibly adjustable. The stacks in the motorized working area are used to match the unstable power inflow. When the renewable energy power generation increases, increase the voltage of the stacks in the motorized working area or increase the number of started stacks; when the power generation of the power generation unit decreases, the stack voltage in the motorized working area can be maintained at a smaller value to avoid energy loss caused by large-area stack start and stop. If necessary, some stacks can also be shut down.

[0036] In some embodiments, a valve 13 is provided at the connection of the gas outlet 317 of the cathode or the gas outlet 316 of the anode of each stack 31 to the pipeline. Through the opening and closing of the valve 13, flexible control of the gas of any stack 31 can be realized, so as to facilitate maintenance or match start and stop situations such as energy storage requirements.

[0037] In some embodiments, a valve 13 is provided at the electrolyte inlet 314 of each stack 31.

[0038] In some embodiments, a pump 14 is provided between the multi-functional cooling water tank 81 and the hydrogen gas-liquid separation tower 61 and the hydrogen scrubbing tower 62 of the hydrogen treatment-related device 6.

[0039] In some embodiments, a pump 14 is provided between the multi-functional cooling water tank 81 and the oxygen gas-liquid separation tower 71 and the oxygen scrubbing tower 72 of the oxygen treatment-related device.

[0040] In some embodiments, a pump 14 is provided between the lye tank 4 and 3.

[0041] In some embodiments, a pump 14 is provided between the total replenishment tank and the multi-functional replenishment tank.

[0042] In some embodiments, the water passing through the first heat exchanger 82 or the water passing through the second heat exchanger 83 that remains after replenishing the total replenishment tank flows back to the multi-functional cooling water tank 81. In some embodiments, a pump 14 may be provided on the pipeline where the water passing through the first heat exchanger 82 or the water passing through the second heat exchanger 83 that remains after replenishing the total replenishment tank flows back to the multi-functional cooling water tank 81, and the remaining water is pumped back to the multi-functional cooling water tank 81 by the pump 14 after replenishing the total replenishment tank with the water passing through the first heat exchanger 82 or the water passing through the second heat exchanger 83.

[0043] In some embodiments, for safety considerations, the devices related to centralized hydrogen separation, purification, and storage (including the hydrogen gas-liquid separation tower 61, the hydrogen scrubbing tower 62, and the hydrogen storage tank 63) and the devices related to centralized oxygen separation, purification, and storage (including the oxygen gas-liquid separation tower 71, the oxygen scrubbing tower 72, and the oxygen storage tank 73) are spatially separated as much as possible and are respectively arranged at both ends of the large-scale electrolytic water plant to minimize potential safety hazards.

[0044] The energy supply system 1 is mainly used for renewable power storage and provides current for electrolyzing water to produce green hydrogen in the stack group 3 of the large-scale electrolytic water to produce green hydrogen system.

[0045] The intelligent adaptive control system 9 is a control system with intelligent information processing, intelligent information feedback, and intelligent control decision-making, which realizes real-time monitoring and adjustment of the states of each stack 31 during operation to adapt to the volatility of renewable energy power generation.

[0046] The rectifier system 2 refers to a device system that converts AC power into DC power. It is composed of multiple components and parts, and its function is to convert the current type to ensure power stability and normal operation; the rectifier system 2 mainly includes transformers, rectifiers, capacitors, filters and voltage stabilizers. The transformer converts the voltage from high voltage to low voltage, and reduces or increases the current as needed; the rectifier converts AC power into DC power; the capacitor is used to store electricity and filter out useless AC components to ensure that the output is pure DC power; the filter is used to filter out clutter and noise in the current to ensure the stability and purity of the output current; the function of the voltage stabilizer is to stabilize the output voltage so that the output DC power can be stably controlled.

[0047] The stack group 3 is a collection of multiple stacks 31 , and the large-scale water electrolysis green hydrogen production system realizes a water electrolysis green hydrogen production reaction in each stack 31 .

[0048] The alkali liquid tank 4 is a container for storing electrolyte and providing electrolyte for the large-scale water electrolysis green hydrogen production system.

[0049] The total liquid replenishment tank 5 is a container for collecting, filtering and adjusting the pH of the electrolyte separated by the hydrogen gas-liquid separation tower 61 and / or the first washing liquid obtained after washing and purification by the hydrogen washing tower 62, the electrolyte separated by the oxygen gas-liquid separation tower 71 and / or the second washing liquid obtained after washing and purification by the oxygen washing tower 72, and the electrolyte after the reaction of the last group of fuel cells in the fuel cell group 3, and re-providing electrolyte to the fuel cell group 3.

[0050] The heat exchanger (also called heat exchanger or heat exchange equipment, namely the first heat exchanger 82 and the second heat exchanger 83 described in the present invention) is a device used to transfer heat from a hot fluid to a cold fluid.

[0051] The multifunctional liquid replenishing tank is a container for filtering, replenishing and adjusting the pH of the electrolyte flowing out of the previous battery stack unit 321, and then providing electrolyte to the next group of battery stacks.

[0052] Beneficial Effects

[0053] Compared with the prior art, a certain embodiment of the utility model includes at least one of the following beneficial effects:

[0054] (1) The large-scale green hydrogen production plant by water electrolysis provided by the utility model has low pollution, low energy consumption and low cost, which is conducive to the large-scale industrialization of hydrogen and oxygen production.

[0055] (2)To meet the current demand for green hydrogen production, we have proposed the design of an "electrochemical plant for green hydrogen production". The large-scale electrolytic water plant for green hydrogen provided by the present utility model integrates multiple large-scale electrolytic water systems again. Each large-scale electrolytic water system connects hundreds of stacks 31 in series and parallel to achieve large-scale hydrogen production, and conducts dynamic, nodal, and centralized management through five material and energy elements in the system (including management of electricity, electrolyte, product hydrogen, product oxygen, and system heat), creatively introducing key nodes of centralized management in the large-scale hydrogen production electrochemical plant, maximizing the efficiency of hardware equipment and energy utilization, reducing costs, and obtaining economies of scale.

[0056] (3)Management of electricity

[0057] Even if the traditional single-stack hydrogen production system contains multiple electrolytic cells, its power is still small and the flexible adjustment range is narrow. Considering the large fluctuations of renewable energy during energy storage, the hydrogen production plant of the present utility model contains an energy storage unit (i.e., the energy supply system 1), and the energy storage unit is mainly used for storing renewable electricity. The electricity generated by renewable energy is first stored in the renewable energy storage system, and after passing through the intelligent adaptive control system 9, it is shunted to the rectification systems 2 of each column and then supplied to the hydrogen production unit for electrolytic water to address the instability of renewable energy power generation. At the same time, the working voltages of the stacks in the hydrogen production electrochemical plant are independently controlled. According to the power generation of renewable energy, the number and voltage of the stacks used for starting can be flexibly adjusted to match the energy storage requirements at different times and address the intermittency and volatility of renewable energy power generation. Specifically, the entire electrochemical plant can be divided into two working areas. One is the flexible working area, which is used to match the unstable power inflow. The stacks in the non-flexible working area maintain a stable working voltage, and the stack voltage in the flexible working area is flexibly adjustable. When the power generation of renewable energy increases, the voltage of the stacks in the flexible working area or the number of starting stacks is increased; when the power generation of the power generation unit decreases, the stack voltage in the flexible working area can be maintained at a small value to avoid energy losses caused by the start and stop of a large area of stacks. If necessary, some stacks can also be shut down. The intelligent adaptive control system 9 is an intelligent response system that can monitor the operating status of each column or each stack, including state parameters such as current, voltage, power, liquid level, and temperature, and adjust the voltage and current distributed to each column or each stack according to the power generation of renewable energy, self-regulate the operating status of each column or each stack, and timely adjust the number of stack startups and shutdowns and the corresponding operating power, so as to match the volatility of renewable energy power generation. In addition, the intelligent adaptive control system 9 can also make a response feedback to the abnormal operation of the stacks in the stack group 3, and stabilize the working state of the entire system by adjusting the operating parameters of other electrolytic cells / flexible area electrolytic cells.

[0058] (4)Management of heat

[0059] In a single alkaline fuel cell, after the electrolyte passes through several electrolyzers and leaves the electrolyzer, it needs to go through gas-liquid separation, filtration, rehydration and other operations before being recycled; the amount of electrolyte flowing through the pipeline in the above process, the processing capacity of nodes such as gas-liquid separation, etc. depends on the working power of the electrolyzer; due to the relatively low production capacity, it is obvious that the laying cost of pipelines, separators and other equipment required per unit production capacity is relatively high. In addition, these electrolytes and gases carry a large amount of waste heat (the outlet temperature is about 80-90°C), which can be recycled in theory; however, in order to utilize the waste heat, heat exchange equipment needs to be laid. Since the gas processing volume of a single electrolyzer is limited and the return investment is relatively low, these waste heats are usually not utilized in traditional single fuel cell systems, resulting in waste. However, in the present utility model, by uniformly collecting the gases generated by multiple fuel cells for heat exchange, the number of heat exchangers can be reduced, the heat exchange cost per unit volume of hydrogen can be significantly reduced, and the waste heat can be effectively collected. Thanks to the integrated scale effect of the electrochemical hydrogen production plant, the gas and liquid flow rates in the pipeline and at each node have increased significantly, providing an opportunity for efficient use of waste heat. Since the working temperature of the electrolyzer is generally 80-90°C, in the utility model, the generated hydrogen and oxygen need to be cooled to room temperature through the first heat exchanger 82 and the second heat exchanger 83 respectively before entering the gas storage tank, and then enter the gas storage tank. The cooling water after heat exchange is uniformly collected and aggregated with the dilute alkali solution obtained by separation and washing, and after filtering and mixing in the total replenishment tank 5, part of it is used for replenishment of the entire system. The waste heat absorbed by the cooling water is used to preheat the replenishment here, reducing energy consumption, and the remaining cooling water is used for reflux and reuse.

[0060] In order to reduce the heat loss of the electrolyte in the pipeline, the same group of battery stacks will be transported through pipelines to share the electrolyte. The alkaline solution is transmitted to the first battery stack unit by pump 14. After the electrolysis is completed in the electrolytic cell, the electrolyte flowing through multiple electrolytic cells is uniformly collected in a multi-functional fluid replenishment tank, and gas-liquid separation, filtration, fluid replenishment dilution and pH control are performed in the tank. After that, it is dispersed to the second group of electrolytic cells for electrolysis to reduce concentration polarization and reduce power consumption. Similarly, the electrolyte is continuously filtered, fluid diluted and pH controlled through the multi-functional fluid replenishment tank for reuse.

[0061] (5) Gas Management

[0062] As for the management of product gas oxygen, the oxygen produced by multiple stacks 31 anodes 312 in the electrochemical green hydrogen production plant is uniformly collected into the oxygen gas separator through a widely connected pipeline network, and gas-liquid separation is completed in the oxygen gas separator; from the outlet of the gas separator, it enters the oxygen washing tower 72 through a pipeline, and after the oxygen washing tower 72 completes the washing and purification, it is cooled to room temperature through the second heat exchanger 83 and enters the oxygen storage tank 73 through a pipeline.

[0063] For the management of the product gas hydrogen, the hydrogen generated by the cathodes 319 of multiple stacks 31 in the electrochemical plant is uniformly collected into the hydrogen gas separator through an extensively connected pipeline network, where gas-liquid separation is completed; from the gas outlet of the gas separator, it enters the hydrogen scrubber 62 through a pipeline. After being scrubbed and purified in the hydrogen scrubber 62, it is cooled to room temperature by the first heat exchanger 82 and then flows into the hydrogen storage tank 63 through a pipeline.

[0064] In the above management of hydrogen and oxygen, since the gases generated by multiple stacks 31 are transported and processed centrally, the gas flow rate in the pipeline and the gas volume processed in the hydrogen / oxygen gas separator are much larger than the gas flow rate or processing volume in a single stack. Through the previous cost accounting of equipment, the electrochemical hydrogen production plant proposed in this patent will obviously generate economies of scale, significantly reducing the hardware and operating costs such as pipeline laying and gas separation operations required for unit volume of hydrogen.

[0065] (6) Management of the electrolyte

[0066] There is a multi-functional liquid replenishment tank between each stack unit 321. The multi-functional liquid replenishment tank can filter, replenish liquid, and adjust the pH of the electrolyte flowing out of the previous stack unit 321, and then provide the electrolyte for the next stack unit 321; the electrolyte of the last stack unit 321 can be collected, filtered, replenished with liquid, and adjusted for pH through the total liquid replenishment tank 5 and then re-flow to each multi-functional liquid replenishment tank to provide electrolyte for the stack group 3 for electrolyzing water. The setting of the multi-functional liquid replenishment tank reduces the electrolyte circulation path and the heat consumed by the circulation.

[0067] The first wash liquid and the second wash liquid discharged from the gas-liquid separation towers and scrubbers at both ends of hydrogen and oxygen, as well as the high-concentration alkali liquid discharged from the last electrolytic cell, will be uniformly collected into the total liquid replenishment tank 5, and after operations such as filtration and pH regulation, they will be recycled. The above centralized treatment can minimize waste liquid discharge, reduce water consumption, reduce system energy consumption, and save costs.

[0068] (7) In addition, to facilitate the management of any stack 31 in the integrated electrochemical hydrogen production plant, valves 13 are provided at the joints where the gas outlets of the cathodes 319 and anodes 312 of each stack 31 are connected to the pipeline. By opening and closing the valves, flexible control of the gas of any stack can be achieved, facilitating start-stop situations such as maintenance or matching energy storage requirements. For safety considerations, the relevant devices for centralized hydrogen separation, purification, and storage (including the hydrogen gas-liquid separation tower 61, the hydrogen scrubber 62, and the hydrogen storage tank 63) and the relevant devices for centralized oxygen separation, purification, and storage (including the oxygen gas-liquid separation tower 71, the oxygen scrubber 72, and the oxygen storage tank 73) are separated as much as possible in space and are respectively installed at both ends of the electrochemical plant to minimize potential safety hazards.

[0069] Term definition:

[0070] In the present utility model, normal temperature or room temperature refers to the ambient temperature, which can be 20°C - 30°C; in some embodiments, it is 22°C - 28°C; in some embodiments, it is 24°C - 26°C; in some embodiments, it is 25°C.

[0071] The term "and / or" should be understood to mean any one of the alternatives or a combination of any two or more of the alternatives.

[0072] The term "plurality" means a quantity of 2 or more, such as 2, 3, 4, or 5, etc.

[0073] The term "green hydrogen" refers to hydrogen produced by renewable energy, and no greenhouse gases are generated during the production process.

[0074] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with that embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] Figure 1 It is a schematic diagram of the internal structure of a single fuel cell stack.

[0076] Figure 2 It is a schematic structural diagram of an electrochemical green hydrogen production plant of a fuel cell stack group 3 formed by connecting 5 fuel cell stack units 321 in series, where each fuel cell stack unit 321 is formed by connecting 4 fuel cell stacks 31 in parallel.

[0077] Figure 3 It is a schematic structural diagram and a partial enlarged schematic diagram of a single fuel cell stack unit 321 formed by connecting 4 fuel cell stacks 31 in parallel.

[0078] Figure 4 It is a schematic structural diagram of 2 fuel cell stack units in a fuel cell stack group 3 formed by connecting 5 fuel cell stack units 321 in series, where each fuel cell stack unit 321 is formed by connecting 4 fuel cell stacks 31 in parallel.

[0079] Figure 5 It is a schematic diagram of a single fuel cell stack system.

[0080] Figure 6It is a schematic structural diagram of the multifunctional liquid replenishing tank 12.

[0081] Figure 7 It is a schematic structural diagram of the multifunctional liquid replenishing tank 12.

[0082] Figure 8 It is a schematic structural diagram of the total liquid replenishing tank 5.

[0083] Figure 9 It is a schematic structural diagram of the total liquid replenishing tank 5.

[0084] Figure 10 It is a process flow diagram of the electrochemically produced green hydrogen plant of the present utility model.

[0085] Figure 11 It is a process flow diagram of the material balance of the present utility model.

[0086] Illustration:

[0087] 1. Energy supply system; 2. Rectification system; 3. Stack group; 31. Stack; 312. Anode; 313. Diaphragm; 314. Electrolyte inlet; 315. Electrolyte outlet; 316. Anode gas outlet; 317. Cathode gas outlet; 318. Backup power supply; 319. Cathode; 320. Plate frame; 321. Stack unit; 3211. First stack unit; 3212. Second stack unit; 4. Alkali solution tank; 5. Total liquid replenishing tank; 51. First filter; 52. First liquid replenishing tank, 57. First gas-liquid separator, 58. First purification device; 6. Hydrogen treatment related device; 61. Hydrogen gas-liquid separation tower; 62. Hydrogen scrubbing tower; 63. Hydrogen storage tank; 7. Oxygen treatment related device; 71. Oxygen gas-liquid separation tower; 72. Oxygen scrubbing tower; 73. Oxygen storage tank; 8. Cooling water system; 81. Multifunctional cooling water tank; 82. First heat exchanger; 83. Second heat exchanger; 9. Intelligent adaptive control system; 12. Multifunctional liquid replenishing tank; 121. Second filter; 122. Second liquid replenishing tank; 123. First multifunctional liquid replenishing tank; 124. Second multifunctional liquid replenishing tank; 125. Third multifunctional liquid replenishing tank; 126. Fourth multifunctional liquid replenishing tank; 127. Second gas-liquid separator; 128. Second purification device; 13. Valve; 14. Pump. Detailed implementation manners

[0088] The following embodiments are further descriptions of the present utility model rather than limitations on the scope of the present utility model.

[0089] All technical terms used in the present utility model have the same meanings as those commonly understood by those skilled in the technical field to which the present utility model belongs. The "and" / "or" used in the present utility model includes any and all combinations of one or more of the related listed items.

[0090] Example 1: Large-scale green hydrogen production plant by electrolyzing water

[0091] Please refer to Figure 2 , as Figure 2 shown, where the OH arrow indicates the flow direction of the lye, the O arrow indicates the flow direction of oxygen, the H arrow indicates the flow direction of hydrogen, and the E arrow indicates the current direction.

[0092] A large-scale green hydrogen production plant system by electrolyzing water includes: a large-scale green hydrogen production system by electrolyzing water, and the large-scale green hydrogen production system by electrolyzing water includes an energy supply system 1, an intelligent adaptive control system 9, a rectification system 2, a stack group 3, a lye tank 4, a total replenishment tank 5, hydrogen treatment-related devices 6, oxygen treatment-related devices 7, and a cooling water system 8;

[0093] The hydrogen treatment-related devices 6 include a hydrogen gas-liquid separation tower 61, a hydrogen scrubbing tower 62, and a hydrogen storage tank 63;

[0094] The oxygen treatment-related devices 7 include an oxygen gas-liquid separation tower 71, an oxygen scrubbing tower 72, and an oxygen storage tank 73;

[0095] The cooling water system 8 includes a multi-functional cooling water tank 81, a first heat exchanger 82, and a second heat exchanger 83;

[0096] The current of the energy supply system 1 passes through the rectification system 2 to supply power to the stack group 3 for electrolyzing water;

[0097] The lye tank 4 can provide electrolyte for the stack group 3 through pipelines to electrolyze water to obtain hydrogen and oxygen. The electrolyzed hydrogen and part of the electrolyte (the electrolyte flowing out with hydrogen) can flow out from the cathode gas outlet 317. The electrolyte and the electrolyzed hydrogen can pass through the hydrogen gas-liquid separation tower 61 for gas-liquid separation. The separated hydrogen can then pass through the hydrogen scrubbing tower 62 for washing and purification. The washed and purified hydrogen can be cooled by the first heat exchanger 82 and then stored in the hydrogen storage tank 63; The electrolyte separated by the hydrogen gas-liquid separation tower 61 and / or the first washing liquid obtained after washing and purification by the hydrogen scrubbing tower 62 can be aggregated, filtered, and pH-adjusted through the total replenishment tank 5, and then re-provide electrolyte for the stack group 3 to electrolyze water;

[0098] The electrolyzed oxygen and part of the electrolyte (the electrolyte flowing out with oxygen) can flow out from the anode gas outlet 316, and then pass through the oxygen gas-liquid separation tower 71 for gas-liquid separation. The separated oxygen can then pass through the oxygen scrubbing tower 72 for washing and purification, and then be cooled by the second heat exchanger 83 and stored in the oxygen storage tank 73; The electrolyte separated by the oxygen gas-liquid separation tower 71 and / or the second washing liquid obtained after washing and purification by the oxygen scrubbing tower 72 can be aggregated, filtered, and pH-adjusted through the total replenishment tank 5, and then re-provide electrolyte for the stack group 3 to electrolyze water;

[0099] The energy supply system 1 is a renewable energy storage system; the energy source of the renewable energy storage system is hydropower, wind power or solar energy;

[0100] The intelligent adaptive control system 9 is an intelligent response system, which can monitor the operating status of each column or each fuel cell stack 31, including state parameters such as current, voltage, power, liquid level, temperature, etc., and adjust the voltage and current distributed to each column or each fuel cell stack 31 according to the renewable energy power generation situation, and self-regulate the operating status of each fuel cell unit 321 or each fuel cell stack 31, and timely adjust the number of fuel cell stacks 31 for starting and stopping and the corresponding operating power, so as to match the volatility of renewable energy power generation. In addition, the intelligent adaptive control system 9 can also make a response feedback to the situation of abnormal operation of the fuel cell stacks 31 in the fuel cell stack group 3, and stabilize the working state of the entire system by adjusting the operating parameters of other fuel cell stacks 31 / mobile area fuel cell stacks 31.

[0101] The multifunctional cooling water tank 81 can store cooling water, and the cooling water in the multifunctional cooling water tank 81 can flow to the first heat exchanger 82 and the second heat exchanger 83 through pipelines; the water passing through the first heat exchanger 82 or the water passing through the second heat exchanger 83 returns to the multifunctional cooling water tank 81 after replenishing the total replenishing tank 5.

[0102] In some optional embodiments, the fuel cell stack group 3 is formed by at least 10 groups of fuel cell stacks 31 connected in series, and each fuel cell unit 321 is formed by at least 10 fuel cell stacks 31 connected in parallel; the fuel cell stacks 31 in each fuel cell unit 321 are connected in parallel through pipelines for supplying electrolyte, the circuits of the fuel cell stacks 31 in each fuel cell unit 321 are independent, and there is a multifunctional replenishing tank 12 between each fuel cell unit 321. The multifunctional replenishing tank 12 can replenish and adjust the pH of the electrolyte flowing out of the previous fuel cell unit 321, and then supply the electrolyte to the next fuel cell unit 321; the electrolyte of the last fuel cell unit 321 can be replenished and adjusted in pH through the total replenishing tank 5 (multifunctional replenishing tank 12M1) and then flow back to each multifunctional replenishing tank 12 to supply electrolyte for the fuel cell stack group 3 to electrolyze water; the total replenishing tank 5 is provided with a first filter 51;

[0103] The fuel cell stack 31 includes a power source, an anode 312, a diaphragm 313, a cathode 319 and a plate frame 320; the fuel cell stack 31 further includes an electrolyte inlet 314, an electrolyte outlet 315, an anode gas outlet 316 and a cathode gas outlet 317;

[0104] The working voltages of the fuel cell stacks 31 in the fuel cell stack group 3 can be independently controlled respectively;

[0105] A valve 13 can be provided at the connection of the gas outlet 317 of the cathode or the gas outlet 316 of the anode of each fuel cell stack 31 to a pipeline;

[0106] Each stack 31 may be provided with a valve 13 at the pipe where the electrolyte flows in;

[0107] A pump 14 may be provided between the multi-functional cooling water tank 81 and the hydrogen gas-liquid separation tower 61 and the hydrogen scrubbing tower 62 of the hydrogen treatment-related device 6;

[0108] A pump 14 may be provided between the multi-functional cooling water tank 81 and the oxygen gas-liquid separation tower 71 and the oxygen scrubbing tower 72 of the oxygen treatment-related device 7;

[0109] The multi-functional liquid replenishing tank 12 includes a second gas-liquid separator 127, a second filter 121 and a second liquid replenishing tank 122; or the multi-functional liquid replenishing tank 12 includes a second gas-liquid separator 127, a second purification device 128 and a second liquid replenishing tank 122;

[0110] The total liquid replenishing tank 5 includes a first gas-liquid separator 57, a first filter 51 and a first liquid replenishing tank 52; or the total liquid replenishing tank 5 includes a first gas-liquid separator 57, a first purification device 58 and a first liquid replenishing tank 52; A pump 14 may be provided between the lye tank 4 and the stack group 3;

[0111] A pump 14 may be provided between the total liquid replenishing tank 5 and the multi-functional liquid replenishing tank 12;

[0112] A pump 14 may be provided on the pipeline where the water passing through the first heat exchanger 82 or the water passing through the second heat exchanger 83 returns to the multi-functional cooling water tank (81) after replenishing the total liquid replenishing tank 5;

[0113] The hydrogen gas-liquid separation tower 61, the hydrogen scrubbing tower 62 and the hydrogen storage tank 63 and the oxygen gas-liquid separation tower 71, the oxygen scrubbing tower 72 and the oxygen storage tank 73 are respectively arranged at both ends of the large-scale electrolyzed water green hydrogen production plant or at the farthest two ends of the large-scale electrolyzed water green hydrogen production plant.

[0114] For the convenience of those skilled in the art to understand, in this Embodiment 1, ten stacks 31 are connected in series to form a stack unit 321, and ten such stack units 321 are connected in parallel for example and calculation. However, those skilled in the art should know that the combination method of the stacks 31 in Embodiment 1 is only an example for those skilled in the art to better understand the technical solution of the present invention. The way of connecting the stacks 31 in series and the stack units 321 in parallel in Embodiment 1 does not limit the technical solution of the present invention. Those skilled in the art can change the number of stacks 31 connected in series and the number of stack units 321 connected in parallel according to this Embodiment 1 (for example, the number of stack units 321 connected in series can be changed to 3, and the number of stacks 31 connected in parallel in each stack unit 321 can be changed to 3). As Figure 2As shown, those skilled in the art can also change the number of series-connected stack units 321 to 5 and change the number of parallel stacks 31 in each stack unit 321 to 4, which should also fall within the scope of the technical solution of the present utility model.

[0115] Assume that the production capacity of a single stack 31 is 1500 Nm 3 / h, the rated current I of a single stack 31 is 17200 A, the rated voltage U of a single stack 31 is 336 V, and the DC power consumption is 4.5 kWh / Nm 3 . Taking ten stacks 31 connected in series as a stack unit 321, the total current of each stack unit 321 is 172000 A, i.e., 172 kA, the total voltage is 336 V, and the hydrogen production capacity is 15000 Nm 3 / h, and the actual power is 67.5 MW, that is, the current passing through the rectification system 2 of each stack unit 321 is 172 kA and the voltage is 336 V.

[0116] If the stacks 31 in the present utility model all reach a production capacity of 1500 Nm 3 / h, then these 100 stacks 31 can reach a hydrogen production capacity of 150000 Nm 3 / h, about 450 MW. If you want to realize the concept of a large-scale factory, the large-scale electrolytic water green hydrogen production system in this embodiment can be integrated and expanded into a factory with higher production capacity.

[0117] Embodiment 2: Material balance

[0118] Please refer to Figure 2 , as Figure 2 shown, where the OH arrow is the flow direction of the lye, the O arrow is the flow direction of oxygen, the H arrow is the flow direction of hydrogen, and the E arrow is the current direction.

[0119] Taking the first multi-functional liquid replenishing tank 123 (i.e., multi-functional liquid replenishing tank M101) between the first stack unit 3211 and the second stack unit 3212 as an example, a material balance is carried out for this important node.

[0120] Assume that the electrochemically produced green hydrogen factory contains a×b stacks 31 in total,

[0121] the production capacity of a single stack 31 is A Nm 3 / h;

[0122] The water consumption required to produce a unit of hydrogen (excluding cooling water) is W 需 m 3 / Nm 3 ;

[0123] the lye flow rate is x times the water consumption,

[0124] Then the liquid outflow rate of the lye tank 4 is F V102出 = xbAW 需 m 3 / h;

[0125] The flow rate F of the electrolyte inlet 314 of each stack 31 电堆进 = xAW 需 m 3 / h;

[0126] The flow rate F of the electrolyte outlet 315 of each stack 31 电堆出 = (x - 1)AW 需 m 3 / h;

[0127] The flow rate F of the inlet of the first multi-functional liquid replenishing tank 123 M101进 = (x - 1)bAW 需 m 3 / h;

[0128] The flow rate F of the liquid replenishing port of the first multi-functional liquid replenishing tank 123 M101补 = bAW 需 m 3 / h;

[0129] The flow rate F of the outlet of the first multi-functional liquid replenishing tank 123 M101出 = xbAW 需 m 3 / h;

[0130] The liquid flowing out of the outlet of the first multi-functional liquid replenishing tank 132 is used for the reaction of the stack 31 in the second stack unit 3212. The above calculations are the required amounts under theoretical conditions.

[0131] Please refer to Figure 2 , Figure 2 , which is an example of the present utility model. The multi-functional liquid replenishing tank 12 includes a first multi-functional liquid replenishing tank 123, a second multi-functional liquid replenishing tank 124, a third multi-functional liquid replenishing tank 125, and a fourth multi-functional liquid replenishing tank 126.

[0132] The first multi-functional liquid replenishing tank 123 (i.e., the multi-functional liquid replenishing tank M101), the second multi-functional liquid replenishing tank 124 (i.e., the multi-functional liquid replenishing tank M102), the third multi-functional liquid replenishing tank 125 (i.e., the multi-functional liquid replenishing tank M103), and the fourth multi-functional liquid replenishing tank 126 (i.e., the multi-functional liquid replenishing tank M104) are also used to regulate the pH of the lye. When the pH is too high or too low, the flow rate at the dilute lye replenishing port needs to be changed accordingly, so that the next stack unit 321 can reach the ideal working condition.

[0133] Example 3: Heat balance calculation

[0134] Perform a heat balance on the first heat exchanger 82 and the second heat exchanger 83. Assume that the production capacity of a single fuel cell stack 31 is A Nm 3 / h, and there are a×b fuel cell stacks 31 in the factory. The production capacity of a single fuel cell stack 31 is A Nm 3 / h; the temperatures of the gas before and after passing through the first heat exchanger 82 and the second heat exchanger 83 are T1 = 90°C and T2 = 30°C respectively, and the temperatures of the cooling water are t1 = 20°C and t2 = 50°C respectively. Then

[0135] The oxygen flow rate F passing through the second heat exchanger 83 O2 = 0.5abA Nm 3 / h;

[0136] From the heat Q = F1·Cp1·(T1 - T2) = F2·Cp2·(t2 - t1), it can be seen that

[0137] F O2 ·ρ O2 ·Cp O2 ·(T1 - T2) = F 水 ·Cp 水 ·(t2 - t1), where the density of oxygen ρ O2 = 1.429 kg / m 3 , the constant-pressure specific heat capacity of oxygen Cp O2 = 0.92 J / (g·K), and the constant-pressure specific heat capacity of water Cp 水 = 4.2 J / (g·K)

[0138] Then the cooling water flow rate F required for the second heat exchanger 83 水 = 0.313abA kg / h = 0.000313abA m 3 / h;

[0139] The hydrogen flow rate F passing through the first heat exchanger 82 H2 = abA Nm 3 / h;

[0140] From the heat Q = F1·Cp1·(T1 - T2) = F2·Cp2·(t2 - t1), it can be seen that

[0141] F H2 ·ρ H2 ·Cp H2 ·(T1 - T2) = F 水 ·Cp 水 ·(t2 - t1), where the density of hydrogen ρ H2 = 0.0899 kg / m 3 , the constant-pressure specific heat capacity of hydrogen Cp H2= 14.3 J / (g·K), the constant-pressure specific heat capacity Cp of water 水 = 4.2 J / (g·K)

[0142] Then the cooling water flow rate F required by the second heat exchanger 83 水 = 0.606abA kg / h = 0.000606abA m 3 / h.

[0143] It can be seen from the calculation results that by collecting the gases generated by multiple stacks for heat exchange, the number of heat exchangers can be reduced, the heat exchange cost per unit volume of hydrogen can be significantly reduced, and the waste heat is effectively collected. The cooling water after heat exchange is collected and summarized together with the dilute alkali solution obtained by separation and washing. After filtration and mixing in the total replenishment tank 5, part of it is used for replenishing the entire system, and the pH is monitored before replenishment to facilitate the pH regulation of the subsequent multifunctional alkali solution M10N. The waste heat absorbed by the cooling water also realizes the preheating of the replenishment here, reducing the energy consumption, and the remaining cooling water is used for reflux and reuse.

[0144] Example 4: Overall plant material balance

[0145] Assume that the electrochemical green hydrogen production plant contains a×b stacks, and the production capacity of a single stack 31 is A Nm 3 / h, then

[0146] The gas flow rate F entering the hydrogen storage tank 63 V104 = abA Nm 3 / h;

[0147] The gas flow rate F entering the oxygen storage tank 73 V101 = 0.5abA Nm 3 / h;

[0148] The liquid flow rate F at the liquid outlet of the alkali solution tank 4 V102出 = xbAW 需 m 3 / h;

[0149] The inlet flow rate F of each stack 31 (m - n) 电堆m-n进 = xAW 需 m 3 / h;

[0150] The outlet flow rate F of each stack 31 (m - n) 电堆m-n出 = (x - 1)AW 需 m 3 / h;

[0151] The total inlet flow rate sum of the multifunctional replenishment tank 12 is: F M10N进 = (x - 1)bAW 需 m3 / h;

[0152] The total flow rate of the liquid outlet of the multi-functional liquid supplement tank 12 is: F M10N出 = xbAW 需 m 3 / h;

[0153] The total flow rate of the liquid filling port of the multi-functional liquid supplement tank 12 is: F M10N补 = bAW 需 m 3 / h;

[0154] The cooling water flow rate F of the first heat exchanger 82 101水 = 0.000313abA m 3 / h;

[0155] The cooling water flow rate F of the second heat exchanger 83 102水 = 0.000606abA m 3 / h;

[0156] The liquid outlet flow rate F of the oxygen end of the multi-functional cooling water tank 81 V103-O2 = 0.000313abA+W 洗O2 +W 分O2 m 3 / h;

[0157] The liquid outlet flow rate F of the hydrogen end of the multi-functional cooling water tank 81 V103-H2 = 0.000606abA+W 洗H2 +W 分H2 m 3 / h;

[0158] The inlet flow rate F of the total liquid supplement tank 5 (i.e., the total liquid supplement tank M1) M1进 = 0.000919abA+W 洗O2 +W 分O2 +W 洗H2 +W 分H2 +(x - 1)bAW 需 m 3 / h;

[0159] The liquid filling and outlet flow rate F of the total liquid supplement tank 5 (i.e., the total liquid supplement tank M1) M1出 = (a - 1)bAW 需 m 3 / h;

[0160] The reflux liquid outlet flow rate F of the total liquid supplement tank 5 (i.e., the total liquid supplement tank M1) M1回 = W 回 m 3 / h;

[0161] Perform a material balance on the total replenishment tank 5 (i.e., the total replenishment tank M1), that is, F 进 = F 出 ;

[0162] Then F M1回 + F M1出 = F M1进

[0163] Therefore, F M1回 = W 回 = 0.000919abA + W 洗O2 + W 分O2 + W 洗H2 + W 分H2 +(x - 1)bAW 需 -(a - 1)bAW 需 = 0.000919abA + W 洗O2 + W 分O2 + W 洗H2 + W 分H2 +(x - a)bAW 需 m 3 / h.

[0164] Appendix Figure 11 is the process flow diagram marked with material balance, indicating the flow information of the corresponding pipelines.

[0165] Example 5: Equipment cost accounting

[0166] Please refer to Figure 5 , Figure 5 which is the connection diagram of each device under the connection of a single cell stack.

[0167] Specifically, we conducted a simple equipment cost accounting for the single cell stack system and the electrochemically produced green hydrogen plant provided by the present utility model. Assume

[0168] the price of a single cell stack 31 is B;

[0169] the price of either the hydrogen gas-liquid separation tower 61 or the oxygen gas-liquid separation tower 71 with the same specification is C;

[0170] the price of either the hydrogen scrubber 62 or the oxygen scrubber 72 with the same specification is D;

[0171] the total price of the oxygen storage tank 73, hydrogen storage tank 63, total replenishment tank 5, alkali solution tank 4, and multi-functional cooling water tank 81 is 5E;

[0172] the price of the first filter 51 is F;

[0173] the price of the pump 14 is G;

[0174] The cost per meter of the pipeline is H (assuming that a total of X meters of pipeline are required for a single stack system. For the sake of simplicity in calculation, we estimate that the electrochemical green hydrogen production plant provided by the present utility model requires a total of abc0X meters of pipeline, where c0 is a correction factor. When the number of stacks 31 in the plant increases, the flow rate of the liquid / gas in the pipeline increases, that is, the utilization rate of the pipeline increases. Therefore, c0 < 1, and c0 decreases as a and b increase).

[0175] Then the total cost S of the single stack 31 system 单 = B + 2C + 2D + 5E + 2F + 4G + H·X

[0176] The total cost S of the electrochemical green hydrogen production plant provided by the present utility model 厂 = B + 2C + 2D + 4E + aF + 5G + H·X·abc0

[0177] According to the single stack 31 system, if the same production capacity as that of the electrochemical green hydrogen production plant is to be achieved, the total cost is S 单-总 = ab*S 单 , then

[0178] S 单-总 - S 厂 =

[0179] As can be seen from the above formula,

[0180] When a = b = 1, S 单-总 - S 厂 =

[0181] When a > 1, b > 1, S 单-总 - S 厂 > 0, and when a and b are larger, S 单-总 - S 厂 is larger, that is, the equipment cost advantage of the electrochemical green hydrogen production plant is more obvious, and the scale effect is generated.

[0182] The above are only the preferred embodiments of the present utility model and are not used to limit the present utility model. For those skilled in the art, the present utility model can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model shall be included within the protection scope of the present utility model.

Claims

1. A large-scale green hydrogen production plant by water electrolysis, characterized in that: include: A large-scale green hydrogen production system by water electrolysis, the large-scale green hydrogen production system by water electrolysis comprising an energy supply system (1), a rectification system (2), a battery group (3), an alkali liquid tank (4), a second liquid replenishment tank (122), a total liquid replenishment tank (5), a hydrogen treatment related device (6), an oxygen treatment related device (7) and a cooling water system (8); The current of the energy supply system (1) passes through the intelligent adaptive control system (9) and is divided into the rectification systems (2) of each column to supply power to the battery group (3) for electrolyzing water; the battery group (3) comprises a plurality of battery units, and a multifunctional liquid replenishment tank (12) is connected between adjacent battery units (321); the multifunctional liquid replenishment tank (12) is used to replenish and adjust the pH of the electrolyte flowing out of the battery unit (321), and to provide electrolyte; The multifunctional liquid replenishing tank (12) is composed of a second filter (121), a second purification device (128), a second gas-liquid separator (127) and a second liquid replenishing tank (122) connected in series; The hydrogen processing related device (6) includes a hydrogen gas-liquid separation tower (61), a hydrogen washing tower (62) and a hydrogen storage tank (63); The oxygen processing related device (7) includes an oxygen gas-liquid separation tower (71), an oxygen washing tower (72) and an oxygen storage tank (73); The cooling water system (8) comprises a multifunctional cooling water tank (81), a first heat exchanger (82) and a second heat exchanger (83), and the cooling water system (8) is used to cool the hydrogen output from the hydrogen scrubbing tower (62) and the oxygen output from the oxygen scrubbing tower (72); The energy supply system (1) supplies power to the battery group (3) for electrolyzing water; The alkali liquid tank (4) is connected to the pipeline of the battery group (3), and the alkali liquid tank (4) is used to provide electrolyte to the battery group (3). The electrolyte passes through the battery group (3) to perform water electrolysis to obtain hydrogen and oxygen; The hydrogen gas-liquid separation tower (61) is used for gas-liquid separation, so as to separate the hydrogen obtained by electrolysis of the fuel cell group (3) and the electrolyte discharged along with the hydrogen; The hydrogen washing tower (62) is used to separate, wash and purify the hydrogen delivered from the hydrogen gas-liquid separation tower (61) to obtain a first washing liquid. The washed and purified hydrogen is cooled by the first heat exchanger (82) and then stored in the hydrogen storage tank (63). The total liquid replenishment tank (5) is used for collecting, filtering and adjusting the pH of the electrolyte obtained by separation in the hydrogen gas-liquid separation tower (61) and the first washing liquid; the electrolyte is obtained by separation in the hydrogen gas-liquid separation tower (61); The oxygen gas-liquid separation tower (71) is used to separate gas and liquid, oxygen obtained by electrolysis of the battery group (3), and electrolyte flowing out with the oxygen; The oxygen washing tower (72) is used to wash and purify the oxygen separated by the oxygen gas-liquid separation tower (71) to obtain a second washing liquid. The oxygen is cooled by the second heat exchanger (83) and then stored in the oxygen storage tank (73). The total liquid replenishment tank (5) is used for the electrolyte separated by the oxygen gas-liquid separation tower (71), and for collecting, filtering and adjusting the pH of the second washing liquid; The main liquid replenishment tank (5) also provides electrolyte to the battery stack (3) for electrolyzing water.

2. The large-scale green hydrogen production plant by water electrolysis according to claim 1 is characterized in that: The large-scale water electrolysis green hydrogen production system also includes an intelligent adaptive control system (9); and, The current of the energy supply system (1) passes through the intelligent adaptive control system (9) and is divided into the rectification systems (2) of each column to supply power to the battery stack group (3) for electrolysis of water; The main liquid replenishment tank (5) is provided with a first filter (51), a first gas-liquid separator (57) and a first purification device (58); Alternatively, a first filter (51) and a first purification device (58) are provided between the hydrogen gas-liquid separation tower (61) and the hydrogen scrubbing tower (62) and the total liquid replenishment tank, and A first filter (51) and a first purification device (58) are provided between the oxygen gas-liquid separation tower (71) and the oxygen washing tower (72) and the main liquid replenishment tank (5). The energy supply system (1) is a renewable energy storage system.

3. The large-scale green hydrogen production plant by water electrolysis according to claim 2 is characterized in that: The energy source of renewable energy storage system is hydropower, wind power or solar power.

4. The large-scale green hydrogen production plant by water electrolysis according to any one of claims 1 to 3, characterized in that: The multifunctional cooling water tank (81) can store cooling water, and the cooling water in the multifunctional cooling water tank (81) can flow to the first heat exchanger (82) and the second heat exchanger (83) through the pipeline; the water passing through the first heat exchanger (82) or the water passing through the second heat exchanger (83) replenishes the total liquid replenishment tank (5) and / or flows back to the multifunctional cooling water tank (81).

5. The large-scale green hydrogen production plant by water electrolysis according to any one of claims 1 to 4, characterized in that: The stack group (3) consists of at least two stacks (31); and / or The battery stack (31) includes a power source, an anode (312), a diaphragm (313), a cathode (319) and a plate frame (320); and / or The battery stack (31) further comprises an electrolyte inlet (314), an electrolyte outlet (315), an anode gas outlet (316), and a cathode gas outlet (317).

6. The large-scale green hydrogen production plant by water electrolysis according to any one of claims 1 to 5, characterized in that: At least one or at least two battery stacks (31) are connected in parallel to form a battery stack unit (321), and the battery stack group (3) is formed by at least two battery stack units connected in series; the battery stacks (31) in each battery stack unit (321) are connected in parallel via a pipeline for providing electrolyte, the circuits of the battery stacks (31) in each battery stack unit (321) are independently controlled, and a multifunctional liquid replenishing tank (12) is provided between each battery stack unit (321), and the multifunctional liquid replenishing tank (12) can filter, replenish and adjust the pH of the electrolyte flowing out of the previous battery stack unit (321), and then provide the electrolyte to the next battery stack unit (321); Finally, the electrolyte of the stack unit (321) can be collected and filtered, replenished and pH adjusted through the main replenishment tank (5) and then flowed back to each multifunctional replenishment tank (12) to provide electrolyte for the stack group (3) to electrolyze water; and / or The multifunctional liquid replenishing tank (12) is provided with a second filter (121) and / or a second purification device (128); and / or The multifunctional liquid replenishing tank (12) is composed of a second filter (121) and / or a second purification device (128), a second gas-liquid separator (127) and a second liquid replenishing tank (122) connected in series.

7. The large-scale green hydrogen production plant by water electrolysis according to any one of claims 1 to 6, characterized in that: The operating voltage of each battery stack (31) in the battery stack group (3) can be independently controlled; and / or Each battery stack (31) in each battery stack unit (321) further includes an independently controlled backup power supply (318); and / or Each cell stack (31) in each group of cell stacks (31) further comprises an independently controlled backup power supply (318), and the current provided by the energy supply system (1) is directly provided to the cell stack (31) for electrolysis or provided to the backup power supply (318) and then provided by the backup power supply (318) to the cell stack (31) for electrolysis.

8. The large-scale green hydrogen production plant by water electrolysis according to any one of claims 1 to 7, characterized in that: A valve (13) is provided at the junction of the cathode gas outlet (317) or the anode gas outlet (316) of each fuel cell stack (31) and the pipeline; and / or A valve (13) is provided at the electrolyte inlet (314) of each battery stack (31).

9. The large-scale green hydrogen production plant by water electrolysis according to any one of claims 1 to 8, characterized in that: The hydrogen gas-liquid separation tower (61), the hydrogen scrubbing tower (62) and the hydrogen storage tank (63) and the oxygen gas-liquid separation tower (71), the oxygen scrubbing tower (72) and the oxygen storage tank (73) are respectively arranged at the two ends of the large-scale green hydrogen production plant by electrolysis of water or at the farthest ends of the large-scale green hydrogen production plant by electrolysis of water.

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